1913] Gee: Behavior of Leeches 291 



2. Reactions op Starved Leeches 



Leeches which had been starved for nearly two months were 

 tested for their general responsiveness. Withovit the influence 

 of external stimulation they tend to remain quiet for long 

 periods of time even under the influence of a fair amount 

 of illumination. When they are in this quiescent state, often 

 several stimulations of the anterior end are necessary to produce 

 a decided response. Upon their being awakened their response 

 shows an increased irritability over that of the normal speci- 

 mens, often upon the second or third stimulation the animal 

 responding with a complete recoil and swimming reaction. In 

 this excited condition only a very slight stimvilus is necessary 

 to set the leech wildly active again. The starved leech seems to 

 be more easily fatigued upon the application of successive stimuli 

 than is the case with the normal individuals. This is due perhaps 

 to much the same reason as the similar phenomenon in higher 

 animals. Lee (1910) sajs: "Exact laboratory investigation 

 shows that if most of the carbohydrate be removed from an 

 animal's body, he presents the symptoms of pronounced fatigue; 



TABLE XVI 



Duration in Seconds of Swimming Response in Normal and Well-Fed 

 Leeches 



